i don't know if this is addressed elsewhere, but for some reason, I play the game and after a while, the graphics freeze. The game itself keeps running, which can be dangerous when this happens in combat, and it is random as to when it happens. Sometimes it'll happen right after i start, sometimes I'll go hours with no issues at all, then get tagged. I used Ctrl-Alt-Del to force it to minimize, then re-size the window and the graphics are running again, like nothing was wrong, then it'll do it again after a while.

If your not using V-Sync, try that.